Pastor Robert Jeffress of First Baptist Church of Dallas has come under fire by creationist Ken Ham, after the Texas preacher suggested that the universe might indeed be 13.7 billion years old, as modern science claims.

"It is so distressing that so many of our Christian leaders don't seem to understand that to accept man's fallible beliefs of billions of years, Big Bang etc, they are really undermining the authority of God's Word," Ham, president/CEO and founder of Answers in Genesis–U.S. and the Creation Museum, wrote on his Facebook page on Thursday.

"To send a signal to coming generations that one can accept such false ideas like the Big Bang and billions of years they are taught at public school and secular colleges (and many compromising Christian Colleges) is a major factor why so many of the coming generations begin to doubt the authority of the Word of God," the creationist added.

Ham was referring to comments Jeffress made earlier this week in his interview on "The O'Reilly Factor" on Fox. The show's host, Bill O'Reilly, and Jeffress debated whether the Bible should be taken entirely literally or not, with the First Baptist Church pastor insisting that in many cases, it can be.

"Absolutely," Jeffress said about the story of Adam and Eve and the Garden of Eden as found in Genesis. "They lived. They were actual human beings, and Jesus affirmed that in Matthew 19, and so I think Jesus knew what he was talking about."

"[But] don't you kind of have to reject the science of evolution and carbon dating, and all of those things?" O'Reilly probed. "So, it's kind of incompatible with science – am I wrong?"

Jeffress, who has been defending his church in recent times over claims by some sections of the media that it is anti-gay and hateful (forcing NFL star Tim Tebow to back out of a speaking engagement there) said that the Bible and science are not opposing forces.

"The Bible does not contradict true science. It may contradict the passing fads of scientific theory that are always evolving. For example, it used to be thought that the cosmos always existed. But, then we had Sir Frederick Coyle, who named the Big Bang Theory, who said, 'Guess what? The universe had a beginning 13.7 billion years ago,'" Jeffress said, adding that he believes that might be true.

"One of the things fundamentalist Christians mess up on is they try to say the earth is 6,000 years old. The Bible never makes that claim," Jeffress added.

The two later agreed that regardless of how one interprets the Bible, following Christ was the most important aspect that rises above all other questions.

Ham, however, who has often been a vocal defender of the Young Earth creation theory, was entirely displeased by the Dallas pastor's comments.

"The Age of the Universe – when Christians accept it is 13.7 billion years old, they are accepting fallible man's dating methods as infallible, and God's Word as fallible," Ham continued on Facebook.

"So Sad this well known pastor publicly came out against those of us who take God at his Word and believe in a young earth/universe. This pastor in my opinion really just sent a signal to the church not to listen to people like those of us at AiG. He really sent a signal not to support the Creation Museum and our resources."

Last year, Ham also criticized evangelist Pat Robertson and famous TV-show scientist Bill Nye who spoke out in separate interviews against the Young Earth Creation Theory.

"You go back in time, you have carbon dating, all these things, and you have the carcasses of dinosaurs frozen in time," Robertson told his "The 700 Club" viewers in November.

"They are out there. And so there was a time when these giant raptors were on the earth and it was before the time of the Bible. So don't try to cover it up and make like everything was 6,000 years, that's not the Bible."

Nye said that he was very happy to hear those remarks from a famous evangelist, and said that "if Mr. Robertson's followers follow him ... it could change the world."

In another Facebook post, Ham warned that such endorsements of modern science by evangelists lead to a dangerous path.

"Not only do we have to work hard to not let our kids be led astray by the anti-God teaching of the secularists, we have to work hard to not let them be led astray by compromising church leaders like Pat Robertson," Ham wrote.